DATAMATH CALCULATOR MUSEUM
Radio Shack EC-1000
|Date of introduction:||1973||Display technology:||Panaplex II|
|New price:||$89.50||Display size:||8|
|Size:||9.0" x 6.6" x 2.6"|
|Weight:||1 pound 12 ounces||Serial No:||D0008494|
|Batteries:||Date of manufacture:|
|AC-Adapter:||120 V||Origin of manufacture:||USA|
|Program steps:||Courtesy of:||Joerg Woerner|
again we had our doubts about the origin of a Radio Shack calculator. This
EC-1000 uses a keyboard similar to the SR-20,
sliding knobs like the TI-410 but looks
totally different to the sibbling TI-3000.
Dismantling a calculator reveals usually within seconds the manufacturer of it, just search a logo on the printed circuit board (PCB), check the main components or think about the mechanical construction. Sometimes we use hints in the manual like the addresses of the Service Facility.
But this EC-1000 was a great exercise !
The internal construction of the EC-1000 looks different to the desktop calculators known from Texas Instruments, but the components are well known:
|The keyboard was manufactured by Texas Instruments|
|The display is a Panaplex II type used in the TI-3000|
|The calculator circuit is a TMS0109|
But finally we found a small number etched on the backside of the PCB and we recognized it: 13-04-709-718. Some other calculators carry numbers with the leading 13-04-709 code and we found the missing link to Texas Instruments with the Montgomery Ward P8F.
|13-04-709-478||Montgomery Ward||P8M||Main board|
|13-04-709-479||Radio Shack||EC-300||Main board|
|13-04-709-504||Montgomery Ward||P8F||Main board|
|13-04-709-544||Montgomery Ward||D12K||Main board|
|13-04-709-698||Montgomery Ward||P8F||Display board|
|13-04-709-718||Radio Shack||EC-1000||Main board|
The rare Montgomery Ward D8F, D10P, and D12K make use of an almost identical housing and very similiar printed circuit boards (PCBs).
portable calculator EC-300 matches the design of this
EC-1000. The successor of the EC-1000 was introduced in 1974 and based on the TI-3500.
Don't miss the rare EC-2000.
If you have additions to the above article please email: firstname.lastname@example.org.
© Joerg Woerner, February 26, 2003. No reprints without written permission.